1. Field of the Invention
The present invention relates generally to vehicles and trailers, and more specifically to vehicles and trailers that travel on a roadway and which are equipped with reflective materials.
2. Background Information
Many countries require vehicles which are used on public roads and thoroughfares to be equipped with light reflectors. In the United States, for instance, the federal government requires vehicles to be equipped with lamps and reflective devices. Elaborate regulations are in place with the goal of crash avoidance. Typically the lights and/or reflectors are positioned on a vehicle to alert oncoming traffic of the presence of the vehicle for safety purposes. These lights and/or reflectors are positioned at various points around the vehicle, such as on either side of the vehicle and/or at the front or rear portions of the vehicle.
The reflectors generally work fine for situations where a vehicle is stopped or stalled on a roadway or side of the roadway, for instance. The headlights of an oncoming vehicle generally cast light off the reflectors which reflects back to the oncoming vehicle. However, a stalled vehicle may not always be positioned upright to allow for reflection. While reflectors may be positioned around the circumference of the stalled vehicle, the bottom of the vehicle may be all that is showing to an oncoming vehicle. Such is the case, for instance, in recent tragic events involving an overturned tractor trailer or semi-trailer vehicle having jackknifed on a highway late at night. Oncoming traffic is unable to see the overturned vehicle or trailer until in close proximity. If the oncoming vehicle is traveling at night and at high speed, a collision is not unexpected. The collision can be tragic. Fortunately, such tragedies can be minimized or avoided altogether with the use of reflective material positioned on the underside (and/or topside) of the stalled vehicle. Thus, even if a vehicle flips over with only a bottom portion visible to oncoming traffic, an oncoming driver may still be alerted of the situation in time to take corrective action. With minimal expense of applying a cautionary device to the underside of vehicles, greater safety can be achieved on our roadways.
All types of vehicles can and should be equipped with such reflectors, including the tractor-trailer example noted above, and automobiles, and busses, and every other type of vehicle or trailer on the roadway. Rescue or recovery workers will also find the invention useful in cases where the vehicles have flipped over, especially at night, or where vehicles are submerged in water or other situations causing difficulty in spotting the vehicle. Being able to span a flashlight across a potential crash site or location to observe a reflection from the invention will allow the quick location of distressed vehicles and faster rescue or recovery of the occupants or the vehicle itself.
There are numerous examples of reflective devices being applied to vehicles. Some inventions for which patents have been granted are found in the following: Coligionis, U.S. Pat. No. 5,210,642; Coligionis, U.S. Pat. No. 5,402,266; Adams, U.S. Pat. No. 7,011,418; Danekas et al., U.S. Pat. No. 5,709,455; Malaguti, U.S. Pat. No. 2,163,380; among perhaps many more.
None of these prior devices, or prior inventions for which patents have been granted, however, include a retroreflective device viewable from the underside of a vehicle, or even recognize that there would be use for such an invention. Further, none of these prior devices include a retroreflector oriented to reflect light away from the vehicle at an angle generally perpendicular to an underside of the vehicle.
The term “retroreflective” as used herein refers to the attribute of reflecting an obliquely incident light ray in a direction antiparallel to its incident direction, or nearly so, such that it returns to the light source or the immediate vicinity thereof. There are three types of reflection. Every surface is a reflector. If light hits a sheet of paper, it is reflected in all directions. This is diffuse reflection. With a mirror, the light reflects from the surface at the same angle (angle of incidence equals the angle of reflection). This is specular reflection. With a retroreflector, light is reflected back in the direction that it came from.
Some vehicles, including tractor-trailers, are subject to numerous laws and regulations in an effort to increase the safety of highway traffic. One example of a regulation that attempts to increase highway safety is 49 C.F.R. Section 571.108 (“the Regulation”). One stated purpose of the Regulation is to enhance the conspicuity of motor vehicles on the public roads so that their presence is perceived and their signals understood, both in daylight and darkness.
One of the requirements of the Regulation pertains to tractor-trailers, and requires the trailers to have retroreflective sheeting, reflex reflectors, or a combination thereof, along, for example, the sides of the trailers. Retroreflective sheeting must consist of a smooth, flat, transparent exterior film with retroreflective elements embedded or suspended beneath the film so as to form a non-exposed retroreflective optical system. Retroreflective sheeting must comply with ASTM D4956 standards, except for photometric requirements, which can be found in FIG. 29 of the Regulation. Numerous types of retroreflective sheeting and reflex reflectors are available to satisfy the Regulation. Applicant is aware of no requirement for use of retroreflective sheeting, reflex reflectors, or a combination thereof, at the underside or topside of the trailers (or any vehicles).